Pharmacology L5 Flashcards
How do drugs work
- drugs must exert some
chemical influence on one or more constituents of cells - there must be non-uniform distribution of drugs within the body
- they interact with specific binding sites to modify the physiological/ biochemical state of cells, tissues and organs
Major targets of drug action are
-Hormones
-Ion channels
-Carriers
-Enzymes
- Membrane receptors
- Nuclear receptors
- DNA
What are the levels of drug action
MOLECULAR
CELLULAR
TISSUE
SYSTEM
Molecular level of drug action
Biomolecules as immediate targets of drugs
Cellular level of drug action
Biochemical constituents in the process of transduction
Tissue level of drug action
Alters organ function
System level of drug action
Alters system function
How do drug-receptor interactions occur
through reversible non-covalent bonds
Drug-receptor interactions
- Highly stable ion-ion electrostatic attraction
- Partial charge dipole-ion electrostatic
- Partial charge dipole-dipole electrostatic
- Low strength van de Waals’ electrostatic attraction between apolar groups
- Hydrophobic interactions of apolar molecules in an aqueous environment
How do most drugs exert their properties
by binding protein domains
Protein targets for drug binding
- Receptors
- Ion channels
- Carrier
- Enzymes
Specificity of drug action
reciprocal or dose-dependent
Reciprocal drug action
Some drugs bind only to certain molecular and cellular targets. Certain molecular and cellular targets recognize only certain classes of drugs.
Dose-dependent specificity of drug action
Increasing the dose of drug will affect molecular targets other than the principal pharmacological one, causing toxic side-effects.
What is an Agonist
Drug that binds and activates its respective receptor.